1. Field of the Invention
The invention relates generally to training devices for exercise, sports, etc., and more particularly to training implements that are swung with the hand, such as baseball/softball bats, racquets, golf clubs, and the like, designed to improve swing timing, power, and/or mechanics.
2. Description of the Related Art
Training bats, racquets, golf clubs, or the like with either a cylindrical or spherical stationary weight are well known. For instance, many a baseball training bat involves “donuts” or other weights which are used primarily to develop strength or to practice and perfect the swinging technique of the hitter. Such structures have included bats having unusual weight distribution as well as bats having removable or movable weights supported therein or thereon.
For example, U.S. Pat. No. 514,420 disclosed a bat in which an impact force multiplying device is provided. The impact device includes an elongated hollow passage defined within the striking end of the bat within which a plurality of weighted spherical balls are freely movable. A closure plug is threadably received at the striking end of the bat closing the passage and captivating the weighted balls within the passage. In an alternate embodiment, an elongated cylindrical sliding weight replaces the spherical balls. The intended function is provided by the change of bat characteristic during swinging as centrifugal force drives the weighted members outwardly from the passage end remote from the striking end to the striking end of the bat.
Another example includes U.S. Pat. No. 3,578,801, which sets forth a practice bat having an elongated hollow bat for baseball practice within which an elongated longitudinal rod is supported. A chamber extends along a portion of the elongated rod and supports a slidable weight thereon. During the swinging of the bat, the centrifugal force drives the weight outwardly toward the striking end of the bat.
While the foregoing devices are useful for their intended purposes, there remains a continuing need in the art for evermore improved practice and training devices.